Do you stick to one game and play it all the way through before starting others?

Or do you have more than one current game and switch between playing them. If so, how many?

It's comfortable for me not to change the game halfway through because I may forget some important details (story, hotkeys etc), have to remember them back and lose some time with it that I don't always have enough.

Playing everything or uninstalling game to make space for new/old/wanted one, occasionally finishing game too... ^

I try to stick to one. But often unless it really hooks me I dabble in a bunch and end up making little progress in any. Sticking to one is by far the best option if I want to actually complete the games.

More than one at the same time, and frankly too many to count. But I also stick to one of those many games every once in a while, not out of principle but when I get hooked and really want to play this and only this at the moment.

The disadvantage to my approach is that I leave many "active" games unplayed for a longer time, if they start to bore me or something else currently interests me more, because nothing is stopping me from switching to other titles then, and when I go back to them after a long, long time, I often have to start from scratch or give up on them, since it's too confusing or unsatisfying to pick up where I left them, halfway through, with me having forgotten half of everything already.

The advantage is that I can try out as many games as I like, which makes it easier and more likely for me to find the ones that I enjoy so much that I end up sticking with them of my own accord and not just due to a sense of "duty". So I finish quite a lot of games regardless, it's just that for every game I finish, several others fall by the wayside.

Depends.

I'll usually stick to one "story game", e.g. I don't start Tomb Raider while I'm still playing Deus Ex. However that doesn't extend to "mechanics games". So I'll still throw in a couple of stages in Dirt Rally ongoing Deus ex playthrough notwithstanding...

I typically play a couple of games at a time, of different genres (one of them almost always a first-person shooter, or stealth, or adventure, maybe horror, the other a puzzle, platform, turn-based or real-time strategy etc.). And I usually try to stick to a game until the end before starting another, although I might take a break and play something else if I feel it's becoming too long or stressful. Sometimes I came back and finish the first one, but in all truth I have a good number of games that I simply left halfway, or even earlier than that. Some of them I feel like I should really resume one day, and I'm planning to do so; but for others, I'm honestly a bit hopeless.

I personally tend to play one single game at time and play it until I get completely bored of it. Experimenting different things, trying to understand it's story and mechanics well, discovering things I had not in previous playthroughs, and so on.

The good about this is that you understand all its mechanics and story with full focus on it, the bad is that when you get bored of, you really do tire of that game for a while - sometimes a long while.

Depending on the game, though, I play two at time, to avoid fatigue. Like others said here a "story focused" game, with a "mechanics focused" game.

I think I've always been like this too, specially with console games in the past, which I remember playing only one game at time ad nauseam, in all it's difficulties, getting secrets, speed running levels... Nowdays I'm not so patient to do this anymore, but I still focus on one game at time more.

Mostly one game only at a time. On rare occasions, I need a break but plan to return in order to finish a game - and even then, I do not enjoy the divided attention this creates, as I'll have the unfinished experience in the back of my mind.

My backlog of unfinished games continues to grow. I usually have to be motivated to finish them, otherwise I lose interest or get frustrated and then cleanse my pallet with another game.

One game until I'm bored.... Then I play another game until I'm bored again and so on X-D. Eventually, I will return to the first game.... Until I'm bored again or I finish the game.

I usually play only one of a game of a genre, but I will also play other games of other genres. For example, switching between a strategy game and an RPG.

I have several games installed, but try to stick to playing one until I either finish or, far more likely can't progress, or not the way I want to, and end up dropping it for a while and starting something else (whether right away or weeks or even a couple of months later, during which time I don't play, or at least don't make progress). And that "for a while" may well mean years, so they're left installed, and sometimes I do pick them back up and continue and even finish, which would become highly unlikely if I'd uninstall them (the games that I didn't reinstall after getting this computer back in 2015 are proof of that).
An exception may be games that I expect to be short, or otherwise to finish relatively quickly, which I may occasionally play in a short break or alternating with a long, demanding "story game" when I have trouble advancing in that but I'm not giving up yet. Or that may also happen if the "main" game is one with clearly separate sections, like separate campaigns or scenarios, in which case I may take a break after finishing one and play something else before continuing with another.

It's risky for me to start another game whilst another is still in progress but it does matter what kind of games are in motion.

Sandbox / open-world games with very long exploration/expected gameplay length are a mistake to leave. If I take a break temporarily and lose momentum and especially forget what I'm "currently doing" in the game, then it's death for that save. Either I'd have to start afresh or uninstall completely.

Turn-based stuff or tactical/stealth games with distinct levels/missions to finish I can leave temporarily without issue. Basically I just finish the mission and come back to do the next another time, no probs.

But in all cases I must be enjoying the game I take a pause in. If I feel any hint of dissatisfaction with the game and I leave it, chances are my opinion of it sours even further in absence even though the opinion may have been unfair.

So it's always safer to play just one at a time whenever possible. But there's been cases where I've had three in progress and eventually finished them all at random.

If I'm playing a story-heavy game, I tend to try and stay with that title to completion... or until I've had enough. In the past I've had too many times with story-heavy games where I tried to play intermittently with other games and completely forgot the story and control scheme of the story-heavy title.